Die casting technology (PDC) is a high and cost-effective production method mainly used in the production of non-ferrous metals. Say no to plagiarism. Get a tailor-made essay on “Why Violent Video Games Should Not Be Banned”? Get an original essayIt is widely used in the manufacturing of automotive components with complex geometry and complex shapes that can be difficult with other conventional manufacturing processes. The article provides an overview of the types of die casting techniques. It also describes recent trends and developments made in die casting technology. Numerical simulation is one of the cost-effective methods used to optimize the casting process. The different simulation methods available for numerical simulation of castings are discussed. The document also describes the use of an integrated CAD/CAE approach and a parametric design approach that facilitates the design process. The study carried out in this article also addresses the importance of residual stresses and their effects on the fatigue life of cast components. The most important tool in the die casting operation is the “die” which consists of the mold cavity where the molten metal is forced under pressure so that the required component is cast. The causes of failure and repair options of the dies were discussed. Keywords - Die casting, numerical simulation, software simulation, residual stresses, die failure. The die casting process is characterized by forcing molten metal at high speed and high pressure through a complex system of gates and channels into the die cavity of the tool called a 'die' [1]. The cavity in the die has the shape to be formed. The process has the ability to produce complex shapes with good dimensional accuracy, good surface finish and high material yields. It is widely suitable for casting non-ferrous metals such as Zn, Cu, Al, Mg, Pb and Sn based alloys. Depending on the pressures used, the die casting process can be of two types, mainly high pressure die casting (HPDC) or low pressure die casting (LPDC). Depending on the injection mechanism used, HPDC is classified into hot chamber HPDC process and cold chamber HPDC process. In the Hot Chamber process, the injection mechanism is placed inside the metal furnace where the components are in constant contact with the molten metal. It ensures minimum contact of metal with air, reducing the risk of gas entrapment defects, but reduces component life. While in the cold room process, the injection system is kept outside the furnace and the metal is poured manually/automatically by means of a ladle. This increases component life but increases the risk of gas entrapment defects [2]. Nearly 70% of aluminum components manufactured today are made using HPDC [3]. HPDC is most widely used in the automotive and communications industries to form thin-walled, complex-shaped, high-quality molded components at low cost [4]. It was found that a number of parameters such as geometric design of the product, design of the channel gate system, die and metal temperatures, flow velocity, flow pattern, Heat flow and solidification rate affect the quality of die castings [5]. A major challenge when designing a matrixis to determine whether or not the final part has defects. A number of software packages such as MAGMA, PROCAST and FLOW 3D, FLUENT, etc. are available for simulation of the casting process. They help in the optimization of design parameters and allow designers to quickly and accurately identify and locate defects that help produce higher quality parts in a shorter period of time [6]. Optimal design of the injection system and die geometry is crucial for homogeneous die filling, which closely affects the final quality of the cast components. The quality of castings produced by die die casting process mainly depends on the filling pattern of the channel and gate system used. A consistent mold filling pattern ensures good quality castings. Additionally, despite the design of the sliding door system, their proper location and size play a very important role in controlling defects such as porosity and cracking. Poor trigger system design typically results in the production of castings with defects such as gas and shrinkage porosity, vents, cold seals, incomplete filling, flow lines, and poor surface finish [7]. These casting defects have been shown to influence the static and fatigue strength of die-cast alloys, limiting the use of castings in critical high-strength applications [8]. Parameters such as filling pattern, pressure, filling rate, cooling rate and solidification have a significant impact on the formation of defects in castings. The most frequently encountered defect in castings is porosity which is very closely related to the casting process parameters and has a significant impact on the cost of the casting process through scrap loss [9]. The mold filling process is a typical liquid-gas two-phase phenomenon. The interaction of molten metal and gas in complex molds plays an important role in the formation of gas entrapment defects. Numerical simulation tools can help in the quantitative prediction of such defects [10]. This also allows us to visualize the gradual cooling from the interior of the casting to the external environment. This helps to understand what changes can be made to the design parameters to achieve a consistent mold fill pattern and optimize the design. The high filling speed, high liquid metal temperature, opacity of the metal mold, and high metal pressure create difficulties during direct visual assessment of the mold filling process. Thus, designing and modifying the slide gate system using numerical simulation depends on the trial and error approach.B. Simulation Methods Available for Numerical Simulation of Die CastingA number of methods and software packages are available for the simulation and analysis of the die casting filling process. Software packages are typically grid-based and use the volume of fluid (VOF) method to track free surfaces [1]. Methods such as finite difference method (FDM), finite volume method (FVM), finite element method (FEM), lattice Boltzmann method (LBM), and smoothed particle hydrodynamics (SPH) are used to solve the fluid flow equations governing mold filling. process. Eulerian techniques include the Mark and Cell (MAC) method, the Level Set method, the Volume of Fluid method(VOF) and the arbitrary Lagrangian Euler method which are used to study free surface flows [10] In the Marker and Cell (MAC) method, Lagrangian markers are placed on the interface at the initial time. As the interface moves and deforms, markers are added, removed, and reconnected as necessary. The evolution of the surface between the different fluids is followed by the movement of the markers in the velocity field. It is difficult to maintain mass conservation and determine good surface interpolation in three dimensions. However, this technique does not suffer from digital diffusion and gives accurate results in two dimensions. In the Volume of Fluid (VOF) method, the volume of fluid in each computer cell is represented using a color function. Using color functions to represent interfaces makes them susceptible to digital diffusion and digital oscillations. According to the advection equations, the volume fractions are updated and the free surfaces of the fluid with fractional volume must be reconstructed for each time step. This type of reconstruction is difficult in three dimensions but due to the relative ease of implementation and its basis in volume fractions, this method is well suited to incorporating other physics and is the most popular and widely used method. used [11]. SPH is a Lagrangian method. method which does not require a grid to calculate its spatial derivatives and uses a compact support interpolation kernel to represent any field quantity in terms of its values ​​at a set of disordered points which are the particles. The computational framework on which the fluid equations are solved is particle flow. Particle information allows calculation of smoothed approximations of the physical properties of the fluid and provides a means of finding gradients of fluid properties. This method is applicable to multidimensional problems and is particularly suited to complex fluid flows due to its Lagrangian nature. Fine details such as plume shape, oscillation frequency and phase as well as the correct relative heights of all free surfaces can be captured using SPH.C. Software tools available for digital simulationDigital simulation results can be validated using analog water experiments or software simulations. Various commercial CAE software packages are available to facilitate the simulation and analysis of flow processes. With the rapid advancement of computer technology, various types of finite element software, including professional casting software and general analysis software, are used in practice around the world. Integration of CAD/CAE die casting system and semi-automatic parametric design of trigger system. With the increasing competitiveness and growing market demand, there is a powerful impact on designers to reduce casting defects and improve die quality, production rate and service life. Based on characteristics such as die casting machine type, casting geometry, and alloy properties, die designers can determine the location, shape, and dimensions of the die casting door system. a matrix using appropriate CAD software packages such as Unigraphics, CREO Parametric, Catia, etc. Through the integration of the CAE package with CAD, parameters such as optimal injection pressure, gate speed, filling time, defects related to the filling process and solidification of the casting,etc. can be obtained [12]. Recent advances have incorporated a parametric design approach into various CAD/CAE systems. In the parametric design approach, varying dimensions are treated as control parameters that allow the designer to modify the existing design by simply changing the parameter values. This approach facilitates the efficient design of part families whose members differ only in dimensions, thereby reducing the work of repeatedly creating parts from scratch, since a single parameterized model can be developed to represent a part family. In parametric design, a database of trigger models (or feature library) is already built and includes the original parametric trigger models built using a 3D CAD tool. These models can be easily retrieved from the database, modified with some specified parameters and locations, and then attached to the diecast part. The parametric design approach thus reduces the time and makes the design update easier and faster [13].E. Residual stresses during molding and their effects on fatigue and fracture. Heating is inevitable in the die casting process and temperature differences in the casting as well as other loading conditions result in the formation of residual stresses. These are the stresses that remain in the casting after it is ejected from the mold cavity. The formation of residual stresses during casting is associated with causes such as temperature gradients due to continuous heating and cooling in casting, prevention of mold contraction, and rapid solidification of the mold [14]. Residual stresses, if present in the casting component, significantly reduce its fatigue life and lead to shape changes and cracking in the castings. However, they can have either a life-enhancing effect (positive) or a life-reducing effect (negative), which depends on the sign of the residual stress relative to that of the applied stress. Tensile residual stresses prove to be the most dangerous because, in service, they lead to fatigue crack initiation and growth [15]. During the cold phase of the die casting cycle, these tensile stresses appear on the surface and lead to local plastic deformation on the die, resulting in nucleation and crack growth [16]. Residual stress measurement can be carried out either experimentally, or often with a combination of simulation using advanced numerical analysis techniques. Optimal die design along with correct machining and heat treatments could keep residual stresses to a minimum [17]. Some of the most common methods of measuring residual stress are x-ray diffraction, hole drilling, and sectioning methods. X-ray diffraction and hole drilling methods are non-destructive but sensitive to microstructure and geometry. However, sectioning is a destructive method very suitable for measuring macrostresses in components. Knowledge of residual stresses is important to analyze their influence on fatigue and rupture performance in order to combat rupture. Different types of tool steels with/without surface treatment are used to make dies. The lifespan of dies and molds in industries is improved through rapid repair of damaged surfaces. The degree and severity of damage is determined by the 34 (2013) 519-535